In the wake of the summit between Chinese President Xi Jinping and US President Donald Trump, the China-US relationship is, in one critical respect, more dangerous than at any time since Tiananmen Square. The reason is not trade friction, tariffs, Taiwan or geopolitical competition – significant as those are. It is the competition over artificial intelligence supremacy, which will reshape every aspect of relations in the coming decade. This is not just a technological contest. It is a contest...